document.write( "Question 79946: 1. If y = a(x - 3)^2 + c and y = (2x - 3)(2x + b) represent the same quadratic function, find a, b, and c. (There are two possibles methods: i) expand both or ii) use the symmetry of the roots around the vertex.) \r
\n" ); document.write( "\n" ); document.write( "- I expanded both equations but I could not simplify the terms.\r
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\n" ); document.write( "\n" ); document.write( "Hello there,\r
\n" ); document.write( "\n" ); document.write( " Thank you in advance for your help. For the following problem, I was able to solve it using method 2, but I do not know how to solve it using method 1.\r
\n" ); document.write( "\n" ); document.write( "Best,
\n" ); document.write( "James
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Algebra.Com's Answer #57330 by Earlsdon(6294)\"\" \"About 
You can put this solution on YOUR website!
\"y%5B1%5D+=+a%28x-3%29%5E2%2Bc\"
\n" ); document.write( "\"y%5B2%5D+=+%282x-3%29%282x%2Bb%29\"
\n" ); document.write( "Expand both equations:
\n" ); document.write( "\"y%5B1%5D+=+a%28x%5E2-6x%2B9%29%2Bc\"
\n" ); document.write( "\"y%5B1%5D+=+ax%5E2-6ax%2B%289a%2Bc%29\"
\n" ); document.write( "\"y%5B2%5D+=+4x%5E2%2B%282b-6%29x-3b\"
\n" ); document.write( "Since these two equations represent the same quadratic function, the corresponding terms should be equal, so comparing term-for-term,...
\n" ); document.write( "First term:
\n" ); document.write( "\"ax%5E2+=+4x%5E2\"
\n" ); document.write( "\"a+=+4\"
\n" ); document.write( "Second term:
\n" ); document.write( "\"-6ax+=+%282b-6%29x\"
\n" ); document.write( "\"-6a+=+2b-6\" Substitute a = 4.
\n" ); document.write( "\"-6%284%29+=+2b-6\"
\n" ); document.write( "\"-24+=+2b-6\"
\n" ); document.write( "\"2b+=+-18\"
\n" ); document.write( "\"b+=+-9\"
\n" ); document.write( "Third term:
\n" ); document.write( "\"9a%2Bc+=+-3b\" Substitute a = 4 and b = -9
\n" ); document.write( "\"9%284%29%2Bc+=+-3%28-9%29\"
\n" ); document.write( "\"36%2Bc+=+27\"
\n" ); document.write( "\"c+=+-9\"
\n" ); document.write( "Check: Substitute a = 4, b = -9, and c = -9
\n" ); document.write( "First equation:
\n" ); document.write( "\"y%5B1%5D+=+4%28x-3%29%5E2%2B%28-9%29\"
\n" ); document.write( "\"y%5B1%5D+=+4%28x%5E2-6x%2B9%29%2B%28-9%29\"
\n" ); document.write( "\"y%5B1%5D+=+4x%5E2-24x%2B%2836%2B%28-9%29%29\"
\n" ); document.write( "\"y%5B1%5D+=+4x%5E2-24x%2B27\"
\n" ); document.write( "Second equation:
\n" ); document.write( "\"y%5B2%5D+=+%282x-3%29%282x%2B%28-9%29%29\"
\n" ); document.write( "\"y%5B2%5D+=+%282x-3%29%282x-9%29\"
\n" ); document.write( "\"y%5B2%5D+=+4x%5E2-18x-6x%2B27\"
\n" ); document.write( "\"y%5B2%5D+=+4x%5E2-24x%2B27\"
\n" ); document.write( "As you can see, the two equations are identical if:
\n" ); document.write( "a = 4, b = -9, and c = -9\r
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